Transmission Fluid Change DIY

[Zulu95]

I put Amsoil synthetic autotranny fluid in my '01 3.0L and so far everything is going fine. It seems the '01 had synthetic Dex iii from new.

[xloverofny]

I was experiencing the transmission jump when shifting down from 2nd to 1st gear, i went to the stealers they advised a software upgrade, if it didnt solve the problem, then i need to replace the transmission.
The $200.00 software upgrade worked for 2 days.
I went to my mechanic, (he services my other cars) with a printed instruction of this post. got the gasket and filter from my local stealer, the oil from the Audi dealer. it has been 5 days now, and so far i drove 200 miles, both hwy n local, (as i am writing this i am knocking on a big piece of wood next to me)no problems,, it took six quarts. the car feels smooth.

Thank you x5 world
Thanks woodvine


2002 4.4

[Bimmer360]

Tomaz,
I have 100K in the clock and about to have my step 4.4i transmission oil and filter changed, but one guy said in a different thread, and i quote: "You need to be careful with changing the fluid on Automatics with 100,000 miles though. Sometimes changing the fluid on high mileage automatics makes for problems that were not there to begin with." Do you know if this is true?

Originally Posted by Tomaz

This is an excellent article on a complete transmission flush including the filter that convinced me to do mine.

http://www.xoutpost.com/x5-e53-forum/...smission+flush

One can see all of the sediment in the bottom of the pan and on the magnets. If you only change fluid, there is a chance of dislodging this sediment and causing transmission failure. If you are going to change fluid I recommend you drop the pan and change the filter too.

[RevJunky]

Originally Posted by Bimmer360

Tomaz,
I have 100K in the clock and about to have my step 4.4i transmission oil and filter changed, but one guy said in a different thread, and i quote: "You need to be careful with changing the fluid on Automatics with 100,000 miles though. Sometimes changing the fluid on high mileage automatics makes for problems that were not there to begin with." Do you know if this is true?

That is what the dealer told me and I think it's complete nonsense. That might have some truth in it if you use the wrong fluid but I doubt changing your using the proper fluid will create any new problems that weren't there to begin with. If there is a major problem, changing your fluid probably won't cure it, it might just delay the inevitable. There is no way to determine if changing the fluid will make the transmission last longer but it's certainly worth the peace of mind that it will.

[Bimmer360]

well thats true. But technically, cleaner fluid always better than dirty fluid, and at 100k, i wouldnt be surpised to see that when i drop my pan.

Originally Posted by RevJunky

That is what the dealer told me and I think it's complete nonsense. That might have some truth in it if you use the wrong fluid but I doubt changing your using the proper fluid will create any new problems that weren't there to begin with. If there is a major problem, changing your fluid probably won't cure it, it might just delay the inevitable. There is no way to determine if changing the fluid will make the transmission last longer but it's certainly worth the peace of mind that it will.

[JCL]

Originally Posted by RevJunky

That is what the dealer told me and I think it's complete nonsense. That might have some truth in it if you use the wrong fluid but I doubt changing your using the proper fluid will create any new problems that weren't there to begin with. If there is a major problem, changing your fluid probably won't cure it, it might just delay the inevitable. There is no way to determine if changing the fluid will make the transmission last longer but it's certainly worth the peace of mind that it will.

As transmissions wear, the clutch pack and band material residue collects in the transmission. Most of it is in the pan, where it sits and is completely harmless. Some of it can be in the valve body, which has many small orfices and valves and controls the transmission operation. It looks like a maze, with check valves, etc. The problem with draining a transmission is that it isn't like an engine, it doesn't all drain down and come out the bottom. You will get something like 40% of it out by draining it, and the rest is in the torque converter, cooler, lines, valve body, etc. To change all of the fluid, you either need a pressure changer, or you need to do multiple manual fluid changes, increasing the % of new fluid each time. When you put in new fluid, and start it back up, you can often dislodge the sediment that is sitting in the valve body. This results in a subsequent transmission failure. It is a well-understood cause of transmission failure.

Theoretically, cleaner fluid is always better than dirty fluid. No one is arguing that. Let's assume you put the correct fluid in, and take that issue off the table. The problem is that you have to go through the process of changing the fluid to get the clean fluid in there, and it is the changing process that causes failures, particularly with high mileage transmissions (which have more sediment in them).

Some believe that the benefits outweigh the risks, and go ahead and change the fluid anyway. Some just aren't aware of the risks. BMW (and some of us) believer that the risks are greater than the benefits, and suggest it be left alone. It is not a cost of maintenance issue, for BMW or whoever is paying, it is a risk issue. I don't believe that dirty fluid is more likely to cause a transmission failure than clean fluid, within reason. I believe that the transmission will probably fail due to electrical sensors, valve body problems, actuators, and wear out, more than due to bad fluid. Cleaner fluid won't prolong the life of any of those components.

There is a history of transmission failures at something greater than 100k miles. I have seen no data that suggests that those failures are due to dirty fluid. I have seen transmission failures soon after the fluid has been changed. Search the board for stories about posters with that experience, who put it down to bad luck that they had a transmission failure "even after they had just changed the fluid"

I do believe in preventative maintenance. I do change fluids where I see a benefit to doing so. I just don't see the logic in changing the fluid in a sealed unit, when the very act of changing it introduces a new failure mode that wouldn't exist if it was left alone. If it gives you peace of mind then it is worth doing it. I would have more peace of mind by not doing it myself. Just my $0.02.

[alpac]

If you had periodically changed the fluid every 30k then it makes sense to keep doing it but I would not touch a high mileage tranny like yours that has never seen an oil change.

[Tomaz]

Originally Posted by Bimmer360

Tomaz,
I have 100K in the clock and about to have my step 4.4i transmission oil and filter changed, but one guy said in a different thread, and i quote: "You need to be careful with changing the fluid on Automatics with 100,000 miles though. Sometimes changing the fluid on high mileage automatics makes for problems that were not there to begin with." Do you know if this is true?

Many transmission failures are related to contaminates in the fluid. Merely changing the fluid without changing the filter and cleaning the pan and magnets can cause the sediment to become dislodged and hasten failure. If your going to change the fluid I would highly reccommend changing the filter and cleaning the sediment. I mentioned to check threads for before and after photos to see the astonishing amount of sediment. Further, newly clean fluid may also cause the transmission to shift more crisply and if the transmission was already going to fail mechanically, it would accelerate this cause. Finally, no one would argue that clean fluid in a transmission is better for the life and performance of the transmission. Good luck

[stalklee]

I called my local dealer today for oil change and I also asked about transmission oil change. But the guy told me that transmission oil change is not recommend because it might cause some issues.

What are issues that he was talking about???

[JCL]

Originally Posted by stalklee

I called my local dealer today for oil change and I also asked about transmission oil change. But the guy told me that transmission oil change is not recommend because it might cause some issues.

What are issues that he was talking about???

Read this thread, particularly post #26 onwards. Feel free to ask any questions after you have read the explanation.